I highly recomend a video called 123 Magic!
They don't call it a "discipline method" but method to obtain more cooperation and less resistance from your children. It sounds corney, and I did not believe the results promised by the method. BUT I had faith, and used the method, and it worked!!!
I have 4 boys, ages 6, 4, 2, and 11 months old. My 6 year old is very strong willed, demanding, bossy, resistant temperement. It took a few months of me consistently implementing it, for the complete results as the tape showed, to be seen in my two older children. It was worth it. I spend less time, even having to scold them, dont spank, and the kids actually like the method. It is a win/win situation!
I borrowed the videos from the school district, and cannot remember the name of the guy who made the tape. Tape 1 is for "start behavior" (example; Start coming in for dinner) Tape 2 is for "stop behavior" (example; Stop debating me) Amazon.com might have them. Remember...123 Magic! What I have implemented at home, also carries over in their behavior at school, and other places whether I am with them or not. Implementing this simple method WILL get the cooperation, respect, friendship, and results you want!